Jessica increases the temperature of a block of ice by 20º. Which integer represents the amount by which Jessica must change the temperature for the block of ice to return to its starting temperature? –40
–20
20
40

-- 20 because block of ice was cold to increase the temperature of block of ice Jessica increase the temperature that is 20 degrees or +20 so to decrease the temperature he / she decrease the temperature or --20

so the answer is -- 20 degree

the answer is b: 18

step-by-step explanation:

use the pythagorean theorem to .

a^2+b^2=c^2

plug 18 for "r"

the 2 legs are 18 and 24

18^2+24^2=c^2

324+576=c^2

900=c^2

c=30

30-12=18

18 is the radius

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