Other things equal,an increase in the equilibrium interest rate will:

A) increase R&D spending.
B) rise when the supply of loanable funds increases.
C) decrease purchases of capital goods and reduce R&D spending.
D) increase bank lending.

An increase in the equilibrium interest rate would make it more expensive for firms to borrow funds to finance investments in capital goods and R&D. This would lead to a decrease in purchases of capital goods and a reduction in R&D spending. Option A is incorrect because an increase in interest rates would reduce R&D spending as it would make it more expensive to finance. Option B is incorrect because an increase in the supply of loanable funds would lead to a decrease in interest rates, not an increase. Option D is incorrect because an increase in interest rates would discourage bank lending due to the increased cost of funds.