How much can a balloon hold?!?!?

i have 6 average sized helium balloons and 15 average sized notecards that will be evenly spaced along the balloons 100 meter lon with tape outside. its also only about 10 degrees F. outside. will the balloon be able to support this without a problem or will it droop? i only need it to stay up for about 20 mins. PLEASE ANSWER!