If you see a link like
bi.ly/3gVQKw3,
please don't press it, its a scam

OML thank you for informing everyone, I'm kinda annoyed by those now

Thanks!

see explanation

Step-by-step explanation:

(1)

Volume (V) of prism = area of triangular end face × length

V = × 4.2 × 4.7 × 6.4 ≈ 63.17 mi³

(2)

Volume of a cuboid = lbh

where l is the length, b the breadth and h the height

l = x, b = 4, h = 9 and V = 972, thus

x × 4 × 9 = 972

36x = 972 ( divide both sides by 36 )

x = 27

(3)

V = area of triangular end × length, thus

× 6 × x × 9 = 234.9

27x = 234.9 ( divide both sides by 27 )

x = 8.7