This problem is partially based on problem 12.5b & 12.5c from Lomax & Hahs-Vaughn, 3rd ed.

Is the following contrast legitimate?
H0:(μ2+μ4)(μ1+μ3+μ5)=0\displaystyle {H}_{{0}}:{\left(\mu_{{2}}+\mu_{{4}}\right)}-{\left(\mu_{{1}}+\mu_{{3}}+\mu_{{5}}\right)}={0}
Question for reflection:  Why or why not?

Using the same means, what coefficients might be used to alter the contrast to yield a legitimate contrast?
H0:\displaystyle {H}_{{0}}:  (μ2+μ4)\displaystyle \cdot{\left(\mu_{{2}}+\mu_{{4}}\right)}- (μ1+μ3+μ5)=0\displaystyle \cdot{\left(\mu_{{1}}+\mu_{{3}}+\mu_{{5}}\right)}={0}


1st coefficient:   
2nd coefficient: