1.В правильной четырехугольной пирамиде SABCD апофема равна20 см.Двугранный угол при основании пирамиды равен 45 градусов. Найдите полную поверхность.
2.В правильной четырехугольной пирамиде SABCDвысота равна 16 см. Двугранный угол при основании пирамиды равен 30 градусов. Найдите полную поверхность.
а) A=25см; B=24 см
б) A=48см; B=125см
S=25*24=600
S=48*125=6000
207.Найдите периметр прямоугольника со сторонами A и B
а) A=12см; B=15см
б)A=34см; В=25см
P=(12+15)*2=27*2=54
P=(34+25)*2=59*2=118
210.Первое слагаемое равно 5460, второе-больше него на 545 десятков, третье - на 46 сотен больше второго, а четвёртое- равно сумме первых трёх слагаемых.Найди сумму всех четырёх слагаемых.
5460+5450=10900 второе число
10900+46000=56900 третье число
5460+10900+56900=73260 четвертое
5460+10900+56900+73260=146520
Russia is one of the largest countries in the world. The vast territory of Russia lies in the eastern part of Europe and the northern part of Asia.
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