Answer:
Part a)

Part b)

Part c)
Speed is more than the required speed so it will reach the top
Explanation:
Part a)
As we know that there is no frictional force while block is moving on horizontal plane
so we can use energy conservation on the block



Part b)
If the track has average frictional force of 7 N then work done by friction while block slides up is given as



work done against gravity is given as



Now by work energy equation we have



Part c)
now minimum speed required at the top is such that the normal force must be zero



so here we got speed more than the required speed so it will reach the top
There is too much information given, it's hard to understand exactly which variables are important in this problem.
Answer:
10
Explanation:
This is tough. The last number 0.2 has only one significant figure. So while the sum of all the numbers is 12.3, you must only leave one sig figure. Rounding to the tenths gives 10.
I believe it is -1.11 m/s^2. I will let you know if its correct