When nuclear fission a. it must be initiated by bombardment with neutrons. b. two nuclei combine to produce a heavier nucleus. c. it is a spontaneous reaction. d. the chain reaction that results cannot be controlled.

Nuclear fission is a process in which a heavy nucleus is broken down into lighter nuclei.

Within a nucleus, the subatomic particles are held together by very strong forces of attraction. Neutrons which have the mass of a proton but no nuclear charges, is used to initiate fission reactions.

For example: The fission of U-235 into Barium (Ba-144) and Krypton (Kr- 89) is initiated by bombardment with neutron

₉₂U²³⁵ + ₀n¹   ⇒    ₉₂U²³⁶            

₉₂U²³⁶  ⇒      ₅₆Ba¹⁴⁴ + ₃₆Kr⁸⁹ + 3₀n¹

Ans) A

Nuclear fission is a process in which a heavy nucleus is broken down into lighter nuclei.

Explanation:

answer: the figure is attached herewith.

step-by-step explanation:   we are given to sketch a unit circle and label the terminal points corresponding to

in the attached figure, we have drawn a unit circle, with centre at o(0,0) and radius 1 unit. we have labelled the points a, b, c, d and e corresponding to the angles below

∠aox = 60°,

∠box = 120°,

∠cox = 180°,

∠dox = 240°,

∠eox = 300°.

and the coordinates are a(0.5,1), b(-0.5,1), c(-1,0), d(-0.5,-1) and e(0.5,-1).

thus, the answer is complete.

explanation:

venn diagram is pictorial representation with of circles showing the relation between two finite sets or things. the intersection part of two circles conveys the relation present in between those sets or things.

here in the venn diagram of sand and salt two circles represent sand and salt. but the area falling under the intersection of these circle represents the mixture of sand and salt.

so, in a venn diagram the mixture will be placed in a middle that is in between the intersection of two circles.