1. Copy and complete the following table in your notebook.
Types of structures Examples
Mass ----------- Walls, dams, etc.
Frame ----------- Structure of a building.
Truss ------------ Cranes, elecricity pylons etc.
Suspended --------- Suspension bridges, tents, etc.
2. Have you ever seen a structure thatr uses cables? Write down the names of the ones that
you can remember or the ones that you can see
and draw them in your notebook.
Tatara Bridge (Japan)
3.When a person sits on a chair, the stress that the chair has to withstand is due to the weight of the person, whereas the strength is the chair´s ability to withstand the load without breaking. Indicate wich i sthe strenght and wich is the strees in these two examples.
a) A wardrobe hanging from a rope.
b) A twisting telephone cord
6. Describe the structure of a turtle´s Shell. Why do you think it has this shape? What material do you think it is made from? Is it stronger enought for the stresses it has to withstand?
It has that shape to protect from predators. It is made of bones.
7. Which types of stressses de the following elements and activitieshave to support : a rope with a wheight hannging of it, a man puishing a cabinet, thingtening a screw, cutting our fingernails.
A rope with a wheight hangining off it-
A man pushing a cabinet-
Thingtening a scerew-
Cutting our finger nails-
9. Write a short description of three objects using one of the following adjectives for each object : rigid, elastic, and plastic. Explain how these properiesallow the objects to fulfil their funcion or make them suitable for their prupose.
Rigid- not pliant or flexible.
Elastic-deformed, compressed.
Plastic- group of synthetic or natural organic materials that may be shaped when soft and then hardened.
11. Copy and complete the following table in your notebook with objects that have propierties shown in the right-hand column
.
Objects Propierties
brick rigid
coffe cup defornable
rubber elastic
chewing gum plastic
Series circuit 
This is a suspended structure.
This is a Truss structure 
Prince was born in Bedford (England) and moved to the community of Fanore in County Clare (Ireland), when she was 2 years old, she emigrated to the United States in 2009 with her mother and four brothers. His mother lived in Boston for some years. According to reports, they chose South Hadley (mass) due to the presence of several family members. Having recently moved to the United States from Ireland, Prince had been harassed and intimidated for several months by at least two different groups of students at South Hadley High School, due to fights with other girls for a brief relationship with a student of football last year and another guy. His aunt claimed that he had warned school in August 2009, before scoring a Prince as a student, which monitor it because it was "susceptible" to intimidation and that had already happened in Irlanda.7 on 14 January 2010, after a whole day of bullying and teasing, followed by a final incident in which a student threw a can from a car as he walked home from school Prince committed suicide by hanging in the stairwell leading to the second floor of the family apartment. His body was discovered by her sister for 12 years. After his death, were many insulting comments on page memorial of Facebook, most of whom were eliminated. His parents decided to bury it in Ireland.
The Internet, sometimes called simply "the Net," is a worldwide system
of computer networks - a network of networks in which users at any one
computer can, if they have permission, get information from any other
computer (and sometimes talk directly to users at other computers). It
was conceived by the Advanced Research Projects Agency (ARPA) of the
U.S. government in 1969 and was first known as the ARPANnet. The original aim was to create a network that would allow users of a
research computer at one university to "talk to" research computers at
other universities. A side benefit of ARPANet's design was that, because
messages could be routed or rerouted in more than one direction, the
network could continue to function even if parts of it were destroyed in
the event of a military attack or other disaster. Every one can have a computer an internet, so its a daangerous thing to log in on some places.