The problem asks to expand the expression $(2a-b)(1+c)$.

1. Problem Description

The problem asks to expand the expression $(2a-b)(1+c)$.

2. Solution Steps

We need to multiply each term in the first parentheses by each term in the second parentheses.

$(2a-b)(1+c) = 2a(1+c) -b(1+c)$

Now, we distribute $2a$ and $-b$ into the parentheses.

$2a(1+c) = 2a(1) + 2a(c) = 2a + 2ac$

$-b(1+c) = -b(1) - b(c) = -b -bc$

Combine the results:

$2a + 2ac - b - bc$

3. Final Answer

$2a + 2ac - b - bc$