Which parallelograms have perpendicular diagonals? rectangle, rhombus square, rhombus square, rectangle none.

Explanation:

Any rhombus has its diagonals meet at 90 degree angles. The proof for this is a bit lengthy, so I'll let you handle it. The basic idea is to draw in the diagonals, which forms smaller triangles. Proving those triangles to be congruent leads to supplementary congruent angles, which in turn leads to the 90 degree angles needed.

A square is a special type of rhombus where all four angles are the same (each 90 degrees). Put another way, a square is both a rectangle and a rhombus at the same time.

Some rectangles are not squares, so the non-square rectangles will have the diagonals not be perpendicular.

it happens during combustion and impacts the environment because the plants and trees take in that and it can cause them to die.

< coa = 150 ( given)

as ba and bc are tangents

so oc and oa is perpendicular to cb and ab respectively because in circle normal passes through centre

so in quadrilateral oabc

< coa + < oab + < ocb + < abc = 360

150 +90+90 + < abc = 360

330 + < abc = 360

< abc = 360 -330 = 30

so < abc = 30

⭐dhruv⭐