Pls someone answer question no. 9 fast plzz..it's urgent

Pls someone answer question no. 9 fast plzz..it's urgent 10 11 12 1 he penmeter one lace 01 a cube is 20 Find the •nd the eube, Marv wants to decorate her Christmas tn.•e She wants to place the tree on a covered with colotm•d with o' Claus She must quantity 0t paper to for this If the box has length 80 breadth 4K' and height then how many square sheets Of paper Of 40 cm would she require? The volume of a cuboid is 3600 cm' and its height is 12 coy The cross-section is a rectangle whose length and breadth are the ratio 4 Find the perimeter oi the cross-sectiorv The •..lume of a cube is 729 cmY Find its surface area and the length of a diagonal length Of the longest whKh can Ex• kept inside a rectangular box is 17 the Inner length and breadth oi tl'w box are 12 cm and 8 cm rwpectively, find its height. A closed rectangular box has inner dimensions cm by 80 cni by 70 cm. its capacity and the area of tin-foil needed to line its Inner surface. The intemal measurements of a box are 20 cm long, 16 cm wide and 24 cm high. How many 4 cm cubes could be put into the box? The Internal measurements of a box are 10 cm long, 8 cm wide and 7 cm hi#,. How many cubes of side 2 cm can be put into the box? Since height of box is 7 cm, only 3 cubes can be put height-wise.

Dear Student,

L e n g t h o f r e c \tan g u l a r b o x, l = 12 c m B r e a d t h o f r e c \tan g u l a r b o x, b = 8 c m L e t t h e h e i g h t o f r e c \tan g u l a r b o x b e h . L e n g t h o f l o n g e s t r o d t h a t c a n b e k e p t i n s i d e a r e c \tan g u l a r b o x = L e n g t h o f d i a g o n a l = \sqrt{l^{2} + b^{2} + h^{2}} 17 c m = \sqrt{12^{2} + 8^{2} + h^{2}} {(17)}^{2} = 12^{2} + 8^{2} + h^{2} 289 = 144 + 64 + h^{2} 289 = 208 + h^{2} 81 = h^{2} h = \sqrt{81} h = 9 c m

Regards