what is the number of hours spent on the project named 'Matter of Time’?
select hours from projects where name = 'A matter of Time'
Find the names of the scientists who worked on this project.
select t3.name from assignedto as t1 join projects as t2 on t1.project = t2.code join scientists as t3 on t1.scientist = t3.ssn where t2.name = 'A matter of Time'
which of those scientists were also involved in the project named 'A Puzzling Parallax'?
select t3.name from assignedto as t1 join projects as t2 on t1.project = t2.code join scientists as t3 on t1.scientist = t3.ssn where t2.name = 'A matter of Time' intersect select t3.name from assignedto as t1 join projects as t2 on t1.project = t2.code join scientists as t3 on t1.scientist = t3.ssn where t2.name = 'A puzzling Parallax'