Answer:
There are basically seven spectral types which are used for classifying the stars and it is arranged in the order of increasing temperature from the hottest temperature to the coldest division are: O, B, A, F, G, K, and M. These categories are basically divided into the sub category in the spectral where O is the hottest type and M is the coldest type.
Answer:
1 casparian strips are present in the root of endodermis.
2 the endarch condition is the character fature of stem.
Answer:
α = 2,857 10⁻⁵ ºC⁻¹
Explanation:
The thermal expansion of materials is described by the expression
ΔL = α Lo ΔT
α = 
in the case of the bar the expansion is
ΔL = L_f - L₀
ΔL= 1.002 -1
ΔL = 0.002 m
the temperature variation is
ΔT = 100 - 30
ΔT = 70º C
we calculate
α = 0.002 / 1 70
α = 2,857 10⁻⁵ ºC⁻¹