I only have 2 theta values of a phase in the tetragonal system.

-Calculate the lattice constants a and c of this phase.

-Determine the cursors of the lines hkl in the chart.

Line	2
Line 1	29.98
Line 2	34.44
Line 3	35
Line 4	50
Line 5	50.42
Line 6	59.12
Line 7	59.92
Line 8	62.6
Line 9	74.3