SQL Taskbook Level 1.7

Given a table:

weather
id date temperature
1 2010-12-01 -15
2 2010-12-02 0
3 2010-06-01 15
3 2010-08-01 -30

Solve the following tasks for it:

Задание 1

Find the sum of the temperature column from this table and make it a positive number.

Задание 2

Select all columns from this table and also select the signs of the temperature column.