Answer:
For number 4: A vector pointing to the right with a magnitude of 2.0
Explanation:
Very simple- just subtract 6-2
I am not sure how to do #2- sorry!
Answer:
-11.11 degree Celsius
Explanation:
The change was 44 degree fanhereit
To 56 degree fanhereit
Therefore the temperature range can be calculated as follows
56-44
= 12 degree fanhereit to Celsius
= 12-32×5/9
= -20×5/9
= 100/9
= -11.11 degree Celsius
Explanation :
The forces acting on hot- air balloon are:
Weight, (W)
Force due to air resistance, (F)
Upthrust force, (U)
Its weight W is acting in downward direction. The upthrust force U acts in upward direction. When the balloon is moving upward, the air resistance is in downward and vice versa.
In this case, the hot-air balloon descends vertically at constant speed.
so, 
and 
so,
....................(1)
when it is ascending let the weight that it is releasing is R, so
..........(2)
solving equation (1) and (2)

2F is the weight of material that must be released from the balloon so that it ascends vertically at the same constant speed.
If I remember correctly (from my studies long time ago) the layers are from the outer to the center:
SiAl : Silicon-Aluminum
SiMa : Silicon-Magnesium (although should be Mg)
NiFe : Nickel-Iron
The SiMa layer should have the lightest elements (Magnesium is lighter than Aluminum)