tolong bantu jawab ya... mtk

a.
r = 3 cm
D = 2.r = 2.3 = 6 cm
s² = r² + t²
    = 3² + 4²
    = 9 + 16
    = 25
s = √25
s = 5 cm

L = π.r.s = 3,14 x 3 x 5 = 47,1 cm²

b.
D = 14 cm
r = 1/2 D = 1/2 . 14 = 7 cm
 s² = r² + t²
    = 7² + 24²
    = 49 + 576
    = 625
s = √625
s = 25 cm
L = π.r.s = 22/7 x 7 x 25 = 550 cm²

c.
r = L/π.s = 188,4/(3,14 x 10) = 188,4 / 31,4 = 6 cm
D = 2.r = 2 . 6 = 12 cm
t² = s² - r²
    = 10² - 6²
    = 100 - 36
    = 64
t = √64
t = 8 cm

d.
D = 7 cm
r = 1/2 D = 1/2 . 7 = 3,5 cm
s = L/π.r = 137,5/(22/7 x 3,5) = 137,5 / 11 = 12,5 cm
t² = s² - r²
    = (12,5)² - (3,5)²
    = 156,25 - 12,25
    = 144
t = √144
t = 12 cm

1) diameter = jari-jari x 2= 3 x2= 6 cm
garis pelukis(s)=√r²+√t²
=√3²+√4²
=√9+√16
=√25
=5 cm

luas selimut= Πrs
=3,14 x 3 x 5
= 47,1 cm²

2) jari-jari= diameter :2= 14:2=7cm
garis pelukis=√r²+√t²
=√7²+√24²
=√49+√576
=√625
=25 cm

luas selimut=Πrs
=22/7x7x25
=550 cm²