Would you be so kind as to help me on these Chemistry problem sets? 
Im having particular issues with the ones below.

Thank you kindly.

01

For an aqueous solution at 25 degrees Celcius, what are the H3O+ and
OH- concentrations of a 0.02 M HCl solution, assuming that HCl is 100
percent dissociated (i.e. strong acid) ?
Answer in the order [H3O+]; [OH-]

a.	1.0 * 10^-7; 1.0 * 10^-7
b.	2.0 * 10^-2; 2.0* 10^-2
c.	2.0 * 10^-2; 5.0 * 10^-13
d.	1.4 * 10^-1; 7.1 * 10^-14
e.	5.0 * 10^-13; 2.0 * 10^-2
02

What is the hydronium ion concentration in a solution having a pH of
0.050 at room temperature?

a.	1.12 M
b.	2.0 * 10^-13 M
c.	0.951 M
d.	3.00 M
e.	0.891 M
03

An aqueous solution is known to have a pH of 5.30 at 25 degrees Celius.
What is the concentration of OH- in the solution?

a.	2.00 * 10^-9 M
b.	1.89 M
c.	8.70 M
d.	5.01 * 10^-6 M
e.	5.01 * 10^8 M
f.	1.00 * 10^-2 M

04

An aqueous solution in which the concentration of OH- is 0.02 M would
be described as

a.	slightly basic 
b.	slightly acidic
c.	very basic
d.	very acidic
e.	neutral

05

What is the [OH-] in a solution of 0.030 M HCl ?

a.	1.0 * 10^-11 M
b.	3.3 * 10^-13 M
c.	3.2 * 10^-10 M
d.	3.1 * 10^-9 M
e.	2.5 * 10^-12 M

06

A 0.010 M solution of a weak acid HA has a pH of 4.20
What is the pOH of the solution? 

a.	7.0
b.	9.80
c.	14.0
d.	4.20
e.	None of these

07

What is the [OH-] in a solution of 0.030 M HCl?

a.	1.0 * 10^-11 M
b.	3.3 * 10^-13 M
c.	3.2 * 10^-10 M
d.	3.1 * 10^-9 M
e.	2.5 * 10^-12 M