ANSWER:
(a) 1036 N
(b) -1036 N
(c) 2590 N
STEP-BY-STEP EXPLANATION:
Given:
Mc = 1400 kg
Mt = 560 kg
a = 1.85 m/s^2
(a)
Force by car on trailer:

(b)

(c)
Answer:
The ratio of the energy stored by spring #1 to that stored by spring #2 is 2:1
Explanation:
Let the weight that is hooked to two springs be w.
Spring#1:
Force constant= k
let x1 be the extension in spring#1
Therefore by balancing the forces, we get
Spring force= weight
⇒k·x1=w
⇒x1=w/k
Energy stored in a spring is given by
where k is the force constant and x is the extension in spring.
Therefore Energy stored in spring#1 is, 
⇒
⇒
Spring #2:
Force constant= 2k
let x2 be the extension in spring#2
Therefore by balancing the forces, we get
Spring force= weight
⇒2k·x2=w
⇒x2=w/2k
Therefore Energy stored in spring#2 is, 
⇒
⇒
∴The ratio of the energy stored by spring #1 to that stored by spring #2 is
2:1