Recent weather forecast in Lushun, Dalian

( 19+22+23+23+ 17+20+2 1+23+24+24)÷ 10,

=2 16÷ 10,

=2 1.6℃

A: The average temperature on 10 day is 2 1.6℃.

(2) Add 19, 22, 23, 23, 17, 20, 2 1, 23, 24, 24,

The order from small to large is: 17, 19, 20, 2 1, 22, 23, 23, 24, 24.

So the median: (22+23) ÷ 2 = 22.5.

Mode: 23 appears three times, so 23 is the mode.

So the answer is: 21.6,22.5,23.