Can someone please help me?

A. Replace the word "and" with "that"

Explanation:

This sentence isn't completely grammatically correct, because we can't properly determine what the part was put forth by Charles Darwin nearly 160 years ago refers to. We could think that it refers to the general theory currently recognized as biology's conceptual framework, when it, in fact, refers to the theory of evolution (is that of evolution = is the theory of evolution). That's why we need to replace the word and with that - so that the given part is more obviously connected to the theory of evolution.

The question is:

Evaluate 6t−20−32u when t=6 and u=1/4

8

Step-by-step explanation:

The given expression is:

We need to evaluate the expression for the given values of t and u. Substituting t=6 and u=1/4 in the above expression we get:

Thus, the give expression is equal to 8 for t=6 and u=1/4