If an English teacher marks 220 essays in 28 hours 36 minutes, how long on average does it take to mark one essay?

First, let us break down 28 hours 36 minutes into minutes.

Number of minutes taken to grade 220 essays = (28 x 60) + 36 = 1680 + 36 = 1716 minutes

Now, we can find the average time taken to grade an essay by dividing the time taken to grade 220 essays by 220.

Average amount of time taken to grade an essay = = 7.8 minutes, or 7 minutes and 48 seconds

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.

6 hours 48 min

step-by-step explanation:

68÷5=13.6

13.6×30=408min=6 hours 48 min.

hope to and hope that my answer is brainliest.(follow me )