Find the measures of the angels of a triangle are represented by x, 4x, and 4x

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is

Will give brainliestbased on the topographic map of mt. st. helens, what is the contour interval if the volcano height is 2,950 m?

Me i'm timed ! a. -2 to 1 b. -1.5 to 0.5c. 0 to 1d. 0.5 to 1.5