Repeat Exercise X6.15, but do not assume equal variances. Are the two sets of results significantly different (test at 5%)? Repeat Exercise X6.16, but do not assume equal variances. Are the expenses...

Repeat Exercise X6.15, but do not assume equal variances. Are the two sets of results significantly different (test at 5%)?

Repeat Exercise X6.16, but do not assume equal variances. Are the expenses claimed by department A significantly different to department B?