heres my answer and reasoning
1) C - the phenomenom described is surface tension, which allows C to occur
2) C - it is important for detegents to be broken down and not cause problems in the environment
3) D - the drugs need to be soluble in order to release their medication, and not neccessarily in the mouth, a lozenge is only one form of drug dispension
4) A - no idea. educated guess, can't be Z cos water isnt an emulsifyer, Y says that a acidifying agent increases the pH but it actually lowers it, W sounded more technical than 'brightens the skin'
5) D - the medication is toxic internally, so by using water as the solvent, it prevents the skin surface being penetrated by water, cos it cant be
6) B - silicone insuitable for large joints, teflon plastic is used as a coating, iron metal is too heavy
7) B - thats what a pacemaker does
8) A - cartilage is a shock absorber in any joint
9) D - CPR wont restart the heart, it simply ensures oxygenated blood is delivered around the body until it can be defibrillated. EAR setablishes normal breathing patterns and we dont want to remove oxygen from the blood
10) B - the others arent true
11) C - encoding changes it from sound into electrical energy, transmitting from electrical into electromagnetic, recieving from electromagnetic into electrical and decoding from electrical into sound energy
12) B - it just does
13) D - A&B are ruled out cos satellite dishes in homes are stationary, C isnt true, both earth and the satellite are moving and D describes a geostationary orbit
14) B - the others are true but cant possibly be concluded from that particular experiment
15) B - there is the same degree of signal loss in both copper wires and optical fibres, just because it is made of glass doesnt mean greater carrying capacity or greater speed. it can only really be B
