Answer:
0.25
Step-by-step explanation:
The marginal rate of technical substitution (MRTS) can be described as the rate of a reduction is one factor to maintain the same production level when another factor is increased.
Given that labor is measured on the horizontal axis, the MRST of K for L can be calculated as follows:

Where;
MPK = Marginal product of capital = 2
MPL = Marginal product of labor = 8
Substituting the values into the equation, we have:

This implies that 0.25 of capital must be given up to have one unit of labor.