Question

19 question please I will mark as brainiest

Answer 1

Answer:

Step-by-step explanation:

In figure,

AB = 9 = c,

BC = 7 = a

AC = 8 = b

Applying cosine formula in △ABC,

CosC = a²+b²−c²/2ab = 49 + 64 −81 / 2 × 7 × 8 = 27  ......[1]

Similarly, using cosine formula in△BMC,

BM² = BC² + CM² − 2BC . CM cos C

Here, CM= CA/2 = 8/2 = 4  {∵ M is the mid−point of AC}

Using [1] ,we have

BM² = 49 + 16 − 2 × 7 × 4 × 27 = 49

⇒BM =7

Now, In △BMP,

we have tanθ = PM/BM =h/7

⇒h/7=tan 15

 => h = 7 tan 15 = 7(2−√3)

Answer 2

Answer:

Plants are the silent workers of our planet, they want to live and also help others (animals including human beings) to live. They have well-developed metabolic system, which includes both anabolism (synthesis) and catabolism (break­down). On the other hand, animals have only catabolic system.

Anabolic system, like photo­synthesis, is present in most of the plants and catabolic system, like respiration, is present in all plants. Photosynthesis is dependent on light, but the respiration occurs both day and night (throughout their life period). Photosynthesis requires CO2, water, chlorophyll and light. Plants can absorb CO2 from the atmosphere and also utilize the CO2 produced from its own respira­tion.