In ΔABC, AB = 24 cm, BC = 10 cm and AC = 26 cm. Is this triangle a right triangle? Give reasons for your answer.
If S is a point on side PQ of a ΔPQR such that PS = QS = RS, then
(A) PR . QR = RS2
(B) QS2 + RS2 = QR2
(C) PR2 + QR2= PQ2
(D) PS2 + RS2= PR2
It is given that ΔABC ∠DFE, ∠A =30°, ∠C = 50°, AB = 5 cm, AC = 8 cm and DF= 7.5 cm. Then, the following is true:
(A) DE = 12 cm, ∠F = 50° (B) DE = 12 cm, ∠F = 100°
(C) EF = 12 cm, ∠D = 100° (D) EF = 12 cm, ∠D = 30°
Can you think of a situation where we deliberately want to make a species extinct? How would you justify it?
In triangles ABC and DEF, ∠B = ∠E, ∠F = ∠C and AB = 3 DE. Then, the two triangles are
(A) congruent but not similar (B) similar but not congruent
(C) neither congruent nor similar (D) congruent as well as similar
The species diversity of plants (22 per cent) is much less than that of animals (72 per cent). What could be the explanations to how animals achieved greater diversification?
Among the ecosystem services are control of floods and soil erosion.How is this achieved by the biotic components of the ecosystem?