Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

A man looks at a painting in a museum and says, “Brothers and sisters I have none, but that man’s father is my father’s son.” Who is in the painting?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

Use the numbers 2, 3, 4 and 5 and the symbols + and = to make a true equation. Conditions: Each must be used exactly once and no other numbers or symbols can be used.

Two prisoners Jack and Jill are locked in a cell.
There is open window approx 40 feet above the ground of the cell.
They are never able to reach there.

Then they plan to escape by a tunnel and they start digging out.
After digging for more than 20 days, Jill comes with the different plan and they escaped.

what was the plan ?

How is the moon similar to a dollar?

By what process could you make a 'Tea-Table' into food?

What word begins and ends with an E, but has only one letter?

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

Cristina leaves home and then she makes exactly 3 left turns and returns home where she found 2 girls wearing the mask.

Who are these two masked girls?