If 20% of some value is 400, then what is the missing value? Is the number 400 a part or a whole

Two lines parallel to the same plane are parallel to eachother

Ann and betty together have $60 ann has $9 more than twice betty’s amount how much money dose each have

The graph shows the decibel measure for sounds depending on how many times as intense they are as the threshold of sound. noise in a quiet room is 500 times as intense as the threshold of sound. what is the decibel measurement for the quiet room? 20 decibels28 decibels200 decibels280 decibels