1.
Answer:
m = 74.9 kg
Step-by-step explanation:
As we know that weight of the object is force due to gravity
Now we know that




2.
Answer:

Step-by-step explanation:
Heat added to the system is given as

so we will have


3.
Answer:
Velocity will increase while acceleration will remain constant
Step-by-step explanation:
When skydiver falls from rest then velocity will increase with time while the acceleration due to gravity will remains constant.
So here we can say that

while velocity will increase while it falls from certain height