Temperature rise in °C
Metal
Mean
temperature
rise in °C
Test 1
Test 2
Test 3
Calcium
17.8
16.9
17.5
Iron
6.2
6.0
6.1
6.1
Magnesium
12.5
4.2
12.3
124
Zinc
7.8
8.0
7.6
7.8
(a) Give two variables the student should control so that the investigation is a fair test
(2)