steps to solve and solution please

Question 5 The 959% confidence interval for a two-tailed independent t-test is 0.2 to 3.7. If the standard error of the difference between the means is equal to 0.4, what is the smallest calculated t-score that would be considered significant? Give your answer to 3 decimal places. Note: it is okay if you enter your answer to 3 decimal places and the system changes it to fewer decimal places (e.g. "1.500" may be changed automatically to "1.5")