Answer:
Ancient cultural artifacts and historical buildings were destroyed.
The answer to this question is - 3
11.
(87+91+86+x)/4=90.
x=96.
13.
50×y > 130.
the lowest number could be 3, because 50×2=120, which is less than 130.
4/5x + 4/3 = 2x....there are 2 ways to do this...one with fractions, one without.
with :
4/5x + 4/3 = 2x
4/3 = 2x - 4/5x
4/3 = 10/5x - 4/5x
4/3 = 6/5x
4/3 * 5/6 = x
20/18 = x
10/9 = x
without :
4/5x + 4/3 = 2x....multiply by common denominator of 15
12x + 20 = 30x
20 = 30x - 12x
20 = 18x
20/18 = x
10/9 = x
1 radian
because s= r × angle measurement in radian
we have s= arc , r = radian so we got the value