**Answer:**

A Trapezoid.

**Step-by-step explanation:**

Imagine the angles as the four corners as 1 (80) being the top left, 2 (100) the bottom left, 3 (100) the bottom right, and 4 (80) the top right.

9514 1404 393

**Answer:**

4 men

**Step-by-step explanation:**

We presume the effort per "m" remains the same.

First project has effort/m of ...

(3 men)(7 h/day)(2 day)/(84 m) = (42/84) man·day/m = 1/2 man·day/m

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Then the number of men required for the second project is ...

(1/2) man·day/m × (256 m)/(8 h/day × 4 day) = (1·256)/(2·8·4) man = 4 man

**It will take 4 men to complete the project in the given time**.

**Answer:**

Factor the following:

3 x^5 - 7 x^4

Factor x^4 out of 3 x^5 - 7 x^4:

Answer: x^4 (3 x - 7)

**Step-by-step explanation:**

**Answer:**

first line third man is army's

**Answer:**

0 , 1 or infinitely many solutions

**Step-by-step explanation:**