Answer: a) 
b) 
Explanation: Visible light is a form of electromagnetic wave.
Wavelength is defined as the distance between two successive crests of a wave. It is represented as symbol
.
Frequency is defined as the number of complete cycles happening per second. It is represented by the symbol
.
Wavelength and Frequency follow inverse relation,

where, c = speed of light = 
Wavelength and frequency of a wave is usually expressed in a range.
a) 
b) 
The reaction between 1 mole of NaOH and 1 mole of HCl creates 1 mole of NaCl and 1 mole of water. Meaning that the moles of HCl needs to equal that of NaOH for the solution to be considered equalized. That being said, you first need to find the numbers miles of HCl by multiplying the volume by the molarity to get 0.01 moles HCl. (1Mx0.01L=0.01). That means that you need 0.01 moles of NaOH. I hope that helps. Let me know if anything is unclear.
The product of the nuclear reaction in which 31p is subjected to neutron capture followed by alpha emission is ²⁸Al.
Nuclear
reaction: ³¹P + n° → ²⁸Al + α (alpha particle).<span>
Alpha decay is radioactive decay in which an atomic
nucleus emits an alpha particle (helium nucleus) and transforms
into an atom with an atomic number that is reduced by
two and mass number that is reduced by four.</span>
Answer: An insulator would be made out of material unable to conduct electricity due to lack of fluid movement for electrons, such as rubber. Rubber properties not only prevents them from freely moving, but also helps electrons stay tightly bound to each other.
Hope this helps ^_^