Step-by-step explanation:
when means of more than two groups are to be compared, ANOVA is perferred
The height of the trapezoid is 2 cm
<span><span><span><span><span><span><span><span><span><span><span><span>(</span></span><span><span><span><span><span><span>1</span></span><span><span>⋅</span></span><span><span>3</span></span></span><span><span>+</span></span><span><span><span>1</span></span><span><span><span>(</span></span><span><span><span><span>5</span></span><span><span>i</span></span></span></span><span><span>)</span></span></span></span></span><span><span><span><span><span>−</span></span><span><span>2</span></span></span><span><span>i</span></span></span><span><span><span>(</span></span><span><span><span><span>3</span></span><span><span>+</span></span><span><span><span>5</span></span><span><span>i</span></span></span></span></span><span><span>)</span></span></span></span></span></span><span><span>)</span></span></span><span><span><span>(</span></span><span><span><span><span>3</span></span><span><span><span>−</span></span><span><span>i</span></span></span></span></span><span><span>)</span></span></span></span></span></span><span><span><span><span>5</span></span></span></span><span /></span><span /></span></span></span></span></span><span>1⋅3+15i-2i3+5i3-i5</span>