What was the time called when the Martinsburg, West Virginia strike spread throughout the mid-west?

Great Upheaval

Explanation: The Great Railroad Strike of 1877, sometimes referred to as the Great Upheaval, began on July 14 in Martinsburg, West Virginia

  180 ft

Step-by-step explanation:

The perimeter of a geometric figure is the sum of the lengths of its sides. Opposite sides of a rectangle are of equal length, so the perimeter can be figured as twice the sum of the length of adjacent sides:

  2(60 ft + 30 ft) = 180 ft

Mrs. Chen needs 180 feet of fence.